Hitherto, in DVDs which are optical disc of large capacity, as information writable optical disc, there are provided DVD-R (DVD-Recordable) which can perform only one write operation, write-once DVD-RW (DVD-Rewritable), DVD-RAM (DVD-Random Access Memory). Among these optical discs, DVD-R and DVD-RW are adapted to record video data by the format in conformity with DVD-video format to thereby have ability to reproduce recorded video data even by reproduction (playback) only optical disc player. Furthermore, in this standard, the standard of Universal Disc Format is supported to thereby have ability to read data on disc by computer.
FIG. 1 is a diagram showing logical format of optical disc by the DVD video format. In the optical disc by this format, as shown in FIG. 1A, the information recording surface is partitioned into Lead-in, Data Zone and Lead-out from the innermost side which is the leading side, wherein desired video data, etc. are recorded in the Data Zone.
Here, the Data Zone is partitioned, from the Lead-in side, UDF (Universal Disc Format) area A1 which is file system area where UDF bridge configuration is described, VMG (Video Manager) area A2 serving as DVD management information area, and real time data recording area A3. The UDF area and the VMG area are management information recording area for performing management of files by video data recorded on the optical disc. Among these UDF and VMG areas, the VMG area which is the second management information recording area is an area corresponding to file management system specific to the DVD video format. Information of TOC which is management information for performing management of the entirety of video data recorded in the real time data recording area A3 is recorded into the VMG area. On the contrary, the UDF area A1 serving as first management information recording area is an area corresponding to the file management system by computer. Management information for performing management of the entirety of video data recorded in the real time data recording area A3 by the format which realizes compatibility with file system in computer is recorded into the UDF area A1.
The real time data recording area A3 is a user area where real data are recorded. As shown in FIG. 1B, video data are recorded into the real time data recording area A3 with VTS (Video Title Set) (hereinafter referred to as title as occasion demands) being as unit. In this example, as far as 99 VTSs can be provided at the maximum (VTS≦99). As shown in FIG. 1C, the VTS consists, from the leading side, VTSI (Video Title Set Information), VTSM VOBS (Video Object Set for the VTSM), VTSTT VOBS (Video Object Set For Titles in a VTS), and VTSI BUP (Backup of VTSI). In the VTSTT VOBS, video data by format of MPEG (Moving Picture Experts Group) 2 which are real data are recorded. In the VTSI, there is recorded recording position information, etc. which is management information for performing management of video data by the real data. In the VTSTT VOBS, title menu of video data is recorded. In this example, VTSTT VOBS is option. VTSI BUP is backup data of VTSI.
Thus, in optical discs of this kind, in the case where access is provided by computer, a desired file is retrieved by UDF to have ability to reproduce the file thus retrieved. Moreover, in the case where such optical disc is reproduced by reproduction only unit such as DVD player, etc., it is necessary to realize compatibility with the reproduction only optical disc. In view of the above as shown in FIG. 1D, there is performed a predetermined processing to form UDF area and VMG area to further form Lead-in and Lead-out. In the case where the optical disc processed in this way is reproduced by the DVD player, a desired file is retrieved by the VMG area to have ability to reproduce the file thus retrieved.
Further, as a system of writing video data onto such optical discs, there are used IncrementalRecording System (hereinafter referred to as INC system) and Restricted Over Write System (hereinafter referred to as ROW system). Here, the INC system is a system of sequentially recording video data, and the ROW system is a system applied to overwritable optical disc. It is to be noted that, also in the ROW system, in the case where data are recorded into unrecorded area, video data are sequentially recorded. In these INC system and ROW system, management of processing with respect to the optical disc such as reservation, etc. is performed by RMA (Recording Management Area) provided at the inner circumferential side of Lead-in.
The recording procedure by the INC system is shown in FIG. 2. In the INC system, it is defined that as far as three areas to be written at a time exist at the maximum. These areas are respectively called R zone, and management of respective R zone is performed by RMA.
Namely, in the case where moving picture (image) is recorded, in the INC system, as shown in FIG. 2A, R zone is first reserved. Here, reservation of R zone is executed by defining area of R zone 1 for forming UDF area and VMG area which are recording area for management information to subsequently define area of R zone 2 for forming VTSI and VTSM VOBS of the leading VTS in unrecorded area for forming real time data recording area to define the remaining unrecorded area as area of Invisible R zone. In the INC system, by reservation of the R zone 1 and the R zone 2, the recording area for management information is ensured, and an area for forming VTSI and VTSM VOBS of the leading VTS is ensured.
In the INC system, video data are recorded in sequence from the leading side of Invisible R zone to thereby form VTSTT VOBS by real data. Further, when recording of real data is completed with respect to one title by instruction of user, VTS1 BUP is recorded subsequently to recording of the real data as shown in FIG. 2B to return to the leading side to form VTS1 and VTSM VOBS in the R zone 2 as shown in FIG. 2C to close the R zone. Thus, in the INC system, one VTS is recorded on the optical disc.
Moreover, in the case where the next title is subsequently recorded, in the INC system, as shown in FIG. 2D, R zone 3 is reserved in the remaining unrecorded area to ensure areas of VTS1 and VTSM VOBS to define Invisible R zone. Further, subsequently thereto, as shown in FIG. 2E, VTSTT VOBS is formed by recording of real data thereafter to form VTSI BUP to form VTS1 and VTSM VOBS in the previously ensured area as shown in FIG. 2F. Thus, in the optical disc, as shown in FIG. 2C, the subsequent VTS is recorded. In the INC system, in the case where title is subsequently recorded, unrecorded area is similarly defined to successively record VTSs.
On the contrary, with respect to the optical disc in which VTSs are successively recorded so that real time data recording area is formed as stated above, in the INC system, as shown in FIG. 2H, recording procedure is executed by forming UDF area and VMG area by finalize processing to further form Lead-in and Lead-out so that compatibility with the reproduction only optical disc is realized. In this case, in formation of the UDF area and the VMG area, data of UDF and VMG are generated from data of VTSI and VTSM VOBS of respective titles to record these data into the R zone 1 to close the R zone 1.
Then, recording procedure by the ROW system is shown in FIG. 3. In the ROW system, as shown in FIG. 3A, recording areas for Lead-in, UDF, VMG and VTSI and VTSM VOBS of leading title are ensured in advance by Padding. Here, the Padding is processing for recording dummy data such as NULL, etc. to ensure areas.
When these areas are ensured in this way, video data are sequentially recorded, as shown in FIG. 3B, in the ROW system to thereby form VTSTT VOBS by real data. When recording of real data has been completed with respect to one title, VTSI BUP is subsequently recorded as shown in FIG. 3B to further execute padding processing for the purpose of ensuring recording areas of VTSI and VTSM VOBS of the subsequent titles. Moreover, subsequently, returning to the leading side, VTSI and VTSM VOBS corresponding to recording of real data are formed as shown in FIG. 3C. Thus, in the ROW system, one VTS is recorded onto the optical disc.
Further, in the case where the next title is subsequently recorded, in the ROW system, as shown in FIG. 3D, succeeding to the padding area formed by VTS immediately therebefore, VTSTT VOBS and VTST BUP are formed by recording of real data to execute padding processing for the purpose of ensuring recording areas for VTSI and VTSM VOBS of the succeeding titles. Further, subsequently, as shown in FIG. 3E, VTSI and VTSM VOBS are formed. Thus, as shown in FIG. 3F, the subsequent VTS is recorded onto the optical disc. In the ROW system, in the case where titles are continuously recorded, processing such as padding, etc. is similarly executed to successively record VTSs.
On the contrary, with respect to the optical disc in which VTSs are recorded in succession in this way so that real time data recording area has been formed, in the ROW system, as shown in FIG. 3G, UDF area and VMG area are formed by finalize processing similar to that of the INC system to further form Lead-in and Lead-out so that compatibility with reproduction only optical disc is realized (Japanese Patent Application Laid Open No. 2001-351314 publication).
Meanwhile, in the case where DVD-video format recording is generally performed with respect to DVD-R or DVD-RW media, file system for performing management of intermediate state is required. If corresponding recording is recording only based on the DVD-video standard, since information for performing management of VTS is also held in the file system in the intermediate state, in the case where VTS is erased, management of position of empty (space) LSN (logical Sector Number) on media is performed. By utilizing such information, it becomes possible to newly make recording at the corresponding position.
For example, there is disclosed a technology in which in the case where information are recorded onto DVD-R along real time, information are recorded in order to have ability to perform reproduction also by player for reproduction only DVD player on which information have been recorded irrespective of real time (Japanese Patent Application Laid Open No. 2002-063765 publication). In this disclosed technology, in the case where information are recorded onto DVD-R while being in conformity with the DVD video standard caused to be of configuration at least including VTS including VOBS and VTSI which are reproduced, and VMGI for controlling reproduction of one or plural VTS or VTSs, VTS is recorded onto the DVD-R to generate temporary VMGI which is temporary control information which corresponds to the recorded VTS and for forming VMGI later to record it onto the DVD-R after recording of VTS to record generated temporary VMGIs onto the DVD-R every time VTSs are recorded onto the DVD-R. As stated above, when unit recording information is recorded, temporary control information is generated to temporarily the temporary control information thus generated onto write-once recording medium, whereby even in the case where plural unit recording information are recorded at the write-once recording medium, primary management control information is precisely recorded later by using temporary control information having the latest content to thereby have ability to execute information recording along real time with respect to the write-once recording medium in conformity with recording format for reproduction only recording medium which is not based on the premise of information recording along real time.
However, there is a demand that extended files are also recorded onto DVD-R media. For example, it is conceivable that such optical discs are applied to portable camera integrated type video recorder in place of magnetic tape. In this case, in the conventional portable camera integrated type video recorders, there are some portable camera integrated type video recorders which can record not only moving picture (image), but also still picture (image). Therefore, also in optical discs of this kind, it is desired that still pictures (images), etc. except for moving picture (image) can be recorded.
Also in the case where such extended file is held at intermediate file system, any management information for recognizing space use state is required. However, there is the problem that management information for DVD-video and/or plural kinds of extended file management information must be referred in order to obtain empty space information so that mounting becomes complicated.
In addition, there is the problem that, in the case of mounting which does not comply with extended file, it becomes impossible to recognize LSN in which recording is subsequently started.
In the case where the DVD disc is used as recording medium and recording is made by the DVD video format, since recording contents are recorded in succession onto the disc, it is necessary to once partition the recording contents as area when kind of recording is different. For example, it is necessary to write information which provides basis of the file system to complete VTS area. However, in such reproduction bridging over the VTS area, management area of reproduction must return to management area of the entirety of the disc to judge next reproduction area. There are instances where some players cannot perform reproduction in a seamless manner in continuous reproduction. Accordingly, it is required to prepare extended areas while continuing areas of the VTS as far as possible.